Adjustable concave.



F, O". BLIXT. ADJUSTABLE GONGAVE.

APPLICATION FILED JAN. 23, 1909.

' 962,1 9%. Patented June 21, 1910.

g I'IIIIIIIII ll 5am 1T4- in L 2 SHEETS-SHEET 1.

P. 0. BLIXT. ADJUSTABLE GONGAVE.

} APPLICATION FILED JAN. 23, 1909. 7 962,192, I v Patented June 21, 1910.

2 SHEETS-SHEET 2.

SAS

FRANK O. BLIXT, OF WORTI-IINGTON, FIINNESOTA.

ADJUSTABLE CONCAVE.

I Specification of Letters Patent.

Patented June 21, 1910.

T all whom it may concern:

Be it known that I, FRANK O. BLIXT, a citizen of the -United States, residing at Vorthington, in the county of Nobles and State of Minnesota, have invented certain new and useful Improvements in Adjustable Concaves, of which the following is a specification.

This invention relates to threshing machines, and more particularly to concaves therefor, and has for its object to provide a concave having teeth adjustable to be thrown out of operative position at times when desired, without checking the operation of the machine.

Another object is to provide a novel means of supporting the adjustable teeth, and a further object is to provide a novel means for moving the adjustable teeth.

Other objects and advantages will be apparent from the following description, and it will be understood that changes in the specificstructure shown and described may be made within the scope of the claim, and that any suitable materials may be used without departing from the spirit of the invention.

In the drawings forming a portion of this specification, and in which like numerals of reference indicate similar parts in the several views, Figure 1 is a sectional view of a detail of a threshing machine transversely of the threshing cylinder, showing all pieces in operative position, Fig. 2 is a similar View showing the adjustable teeth out of operative position, Fig. 3 is a perspective view of a portion of the concave and protective grate, Fig. 4 is a bottom plan view of the concave, the tooth supporting members being removed.

Referring to the drawings, there is shown a portion of a threshing machine having a transverse cylinder 10 beneath which there is located a concave 11, the cylinder and concave being provided with opposed teeth 11 of any suitable type. The concave comprises a base casting 12, rectangular in plan, and supported by suitable means 13 for vertical adjustment to vary the space between the concave and the cylinder 10. The concave is provided with a plurality of longitudinally spaced slots 13, which thus form grate bars 14. The bottom portion of the casting is recessed as shown at 11, certain of the bars 14 being extended to the base of the casting as shown, to provide a support for an operating mechanism subsequently to be described. Fixed in the upper face of the casting 12, there is a plurality of pairs of teeth 11, each pair being disposed in line with an adjacent slot 13. Registering passages 16 are formed through the end walls 17 and the downwardly extending portions 14: at opposite sides of the casting 12, and carry revolubly therein, a shaft 18 upon which there are pivotally engaged opposed movable concave sections 19 movable in the slots 13, and carrying teeth 11.

Spaced passages 20, similar to those at 16 are formed inwardly of the first named passages, nearer the bottom of the casting, having revolubly engaged therein shafts 21 carrying cams 22 adapted to engage beneath the sections 19 for movement thereof into and out of operative position. The shafts 21 carry at their outer ends, operating arms 25 from which there extend rods 26 to a suitable point on the threshing machine for operation in any suitable manner to actuate the cam members 22. The rods are independently operable, so that either of the sections 19 may be operated, as desired.

It will be evident from the foregoing that the use of this concave in the operation of the threshing machine may be modified to suit different kinds and conditions of grain, and in the event that the machine should become clogged, its cleaning is greatly simplified.

It will be noted that the shafts 21 are rectangular in cross section, and the cam members 22 have rectangular passages formed therethrough to engage slidably over the shafts. Set screws 28 are engaged through the members 22 in impingement against the shaft 21 to retain the cam members against displacement. It will be noted that the opposite ends of the slots 13 are extended inwardly of the casting 12, to form a shoulder 29, adjacent the shaft 18. The concave sections 19 are provided with corresponding recesses adapted to engage against the shoulders 29 to check upward movement of the concave when flush with the upper surface of the bars 14L.

What is claimed is A concave for threshing machines comprising a base casting having a plurality of spaced teeth, said casting having a p1u-' ing movable to lie at times flush with the upper face of the concave and being mov able out of operative position, cam members mounted beneath the sections and means for rocking the cam members for vertical movement of the concave sections.

In testimony whereof I aflix my signature, in presence of two Witnesses.

, FRANK BLIXT. Witnesses:

PETER THOMPSON, b. KINDLUND. 

